I decided te make a tutorial about how to make a background. It will be based on the current one, but feel free to modify it how you see fit.
Also please note that this tutorial will be catered to beginners. Advanced Photoshop users will still be able to learn something from this however!

First, we need a general idea of what to do. I wanted a stripy background that fades to black with a possible cross hatch like pattern on it.

Got to: File - new (ctrl-O), and make it 3000 pixels long, and around 200 wide.

This will be the background. The idea is to have it tiles across the entire width of the screen, and have it fade to back, or the colour that you want.

Now import the colorfull picture to your canvas.

You can just drag it on Photoshop, and then drag the picture's layer onto your background canvas, or you can copy it from your browser, and then simply paste it onto your canvas in photoshop.
Now that we have that setup, lets get going with the cool stuff!

Select the Rectengular Marquee Tool (M) and drag a narrow strip over an area you like. Then hit Layer - New - Layer via Copy (Ctrl-J) in order to copy your selection to a new layer.

If you dragged it horizontal, just use Free Transform (Ctrl-T) to rotate it vertically. If you hold shift while you rotate it will snap at 45 degree angles, making sure you dont skew it. (Or just go Edit - Transform - Rotate 90°.)

Now use the Free Transform (Ctrl-t) to stretch the new layer waaaaaaay out. Make sure you at least cover the entire width of you canvas.

This will give you a lot of stripes!! repeat the proces a couple of times to get more variety. Import some more pictures and get samples from them.

Fill the entire height of the canvas with stripes. When satisfied, select all the layers that make up the stripes and click Layer - Merge Down (Ctrl-E).

This will merge all the loose layers to one. Now we will change the colours up a bit.

Copy (Ctrl-J) the stripes layer, and flip it. Either with the Free Transform tool, or by going to Edit - Transform - Flip Vertical. Now set the layer blending options to Multiply.

Feel free to change it up here. If you want to modify some stuff or don't be afraid to experiment around!!

That was all for now, join me again next time for Part 2 of this tutorial where we will make the background fade and add a nifty pattern to it!!

See you next time, and as always, leave your comment, feedback and critics in the comments.

Somehow your blog's subtitle matches this remix quite well. This is a nifty way to create new backgrounds, and even to play around with paths and tools being applied along paths. I shall follow you to get more inspiration for my own projects!